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fxus63 kmpx 171647 

Area forecast discussion
National Weather Service Twin Cities/Chanhassen Minnesota
1147 am CDT Thu Oct 17 2019


Updated to include 18z aviation discussion below.


Short term...(today through friday)
issued at 334 am CDT Thu Oct 17 2019

Clouds will persist this morning across west central Wisconsin as
a weak disturbance moves southeast across the western Great Lakes.
Otherwise, a surface ridge that is currently across eastern
Minnesota this morning, will move off to the east with southerly
winds developing. These southerly winds will increase overnight,
and Friday as another storm system moves out across The Rockies,
and into the plains. Temperatures will be close to guidance with
highs near seasonable norms today, and slightly above normal on
Friday. I wouldn't be surprised to see a 70 degree reading on
Friday if less cloud cover exists.

Long term...(friday night through wednesday)
issued at 334 am CDT Thu Oct 17 2019

The period will commence with a north-south oriented cold front
sweeping across Minnesota Friday evening, continuing its way through Minnesota
and into WI by Saturday morning. This will effectively end the
unseasonably warm air surge into the region. While cold air
advection will not be strong behind the system, there will be a
slight drop in temperatures going from Friday into Saturday. In
addition, this frontal passage will have some modest upper level
support in the sense that barely sufficient deep south moisture
with this front may be able to produce a few rain showers mainly
along and east of I-35 Friday night through Saturday morning.

Once past this system, attention turns to the significant upper
level wave dropping south from the Gulf of Alaska and into the
Pacific northwest Friday through Saturday. This trough will drop into The
Rockies by early Sunday, aiding in surface cyclogenesis over the
Lee of The Rockies between WY/co. This system, already fairly
moisture-laden with Pacific moisture, will be able to draw up
plenty of Gulf moisture well into the upper Mississippi River
valley by Sunday evening. The trough is also expected to deepen
quite well over Minnesota/WI Sunday night into Monday as it merges with
another upper level wave sagging south on the western fringes of
Hudson Bay. This will allow the surface system to become stacked
and well-organized in western Ontario province with the surface
low dropping to near 980mb. Plenty of rainfall is likely with this
system late Sunday through Monday.

As the rainfall ends, the next problem will be another prolonged
period of elevated surface winds. The surface low will become
anchored in western Ontario Monday night through Wednesday. In
conjunction with the slowed progression of the surface low, high
pressure over the western Continental U.S. Behind this system will slowly
slide into the south-central Continental U.S.. a strong pressure gradient
will develop between these large synoptic features, producing
strong winds from the northern plains through the Great Lakes.
Sustained wind speeds will run in the 15-25kt range with gusts
upwards of 35kt, with the highest speeds expected Monday afternoon
through Tuesday evening. Wind speeds will settle down Wednesday
as the large system to the northeast of the weather forecast office mpx coverage area
is nudged further north into eastern Canada while another fast-
moving low pressure system approaches from the Pacific.

As noted earlier, temperatures will remain cool throughout the
extended period, although not cool enough to produce any
appreciable snow showers of any significance through the middle of
next week.


Aviation...(for the 18z tafs through 18z Friday afternoon)
issued at 1150 am CDT Thu Oct 17 2019

Little issues this period. VFR trend with mix of mid/high level
clouds moving in mainly overnight. Increasing southeast-S winds ahead of
incoming developing cold front over the Dakotas. Some gusts around
25kts developing tonight and continuing into Friday morning. Will
continue to mention low level wind shear potential most sites developing mainly
06z-14z Fri with increasing southerly flow.

Kmsp...will continue to mention low level wind shear potential before and through
the Friday morning push. Winds in the 1-2 kft level will increase
to around 40kt from the south, creating a strong vector
difference with surface winds around 10 kt from the southeast. Otherwise
VFR trend.

/Outlook for kmsp/
Fri night...VFR. Chance rain showers. Wind south-southeast at 20g30 kts, bcmg west at 10-15
kts late.
Sat...VFR. Rain showers possible late. Wind west 5-10 kts.
Sun...VFR with MVFR/IFR/-shra late. Winds southeast at 15g25 kts


Mpx watches/warnings/advisories...

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